Studies on the cracking in the tomato fruits. II

Abstract

The objects of this study were to examine the varietal difference of tomato in fruit cracking, and to clarify the characters associated with the occurrence of cracking. 1. Most of the early varieties, such as Bonny Best and June Pink, showed a high percentage of, concentric and irregular crackings. In varieties having less cork layer on their fruits, such as Rot Köppen, San Marzana and Shugyoku, less radial crackings occurred. Concentric cracks developed quite frequently in the varieties having small leav es and exposed fruit clusters. 2. Occurrence of less radial crackings in Crack-Proof and _??_ 135 is considered to be due to high elasticity of fruit skin and to low sugar content of the fruits. 3. Occurrence of less concentric crackings in Crack-Proof and 63A311 is considered to be due to large leaves developing just above the fruit clusters. 4. It is concluded that for breeding strains with less fruit crackings it is desirable to select the plants having large leaves covering the fruit clusters, small stem scar on fruits, and with highly elastic fruit skin.